(a) Field of the Invention
The present invention relates to an an insecticidal composition isolated from plants, and more particularly, to crude extracts and chemical compounds from plants having insecticidal activity against mites or stored-product insects.
(b) Description of the Related Art
Mites are a significant cause of allergies, and in particular they cause bronchial asthma and nasal inflammation. Mites belonging to the Pyroglyphidae family inhabit dust. Dermatophagoides pteronyssinus, D. farinae, D. microceras, and Euroglyphus maynei cause atrophic symptoms such as bronchial asthma, nasal inflammation and eczema.
House dust mites have been found in carpets, clothes, furniture, mattress and bedclothes. House dust mites are distributed not only in temperate regions but in nearly all places of residence.
It has been reported that lindane, pirimiphos-methyl, benzyl benzoate, dibutyl phthalate and diethyl m-toluamid have an acaricidal effect (Hellet-Haupt A. and J. R. Busvine. 1974. Tests of acaricides against house dust mites (Dermatophagoides pteronyssinus, Dermatophagoides farinae). J. Med. Entomol. 2(5):551-558). Lindane is the most acaricidally effective and long-lasting, but due to toxicity its use has been restricted for homes. The second best acaricidal compound among the above compounds, pirimiphos-methyl, has low toxicity against mammals, and it has been put to a practical use in order to control mites inhabiting storage grain. It was reported that pirimiphos-methyl was able to control 60% of mites inhabiting carpets, and 50% of mites inhabiting chairs (Mitchell, E. B., S. Wilkins, J. McCallum Deighton and T. A. E. Platts-Mills. 1985. Reduction of house dust mite allergen levels in the home: use of the acaricide, pirimiphos methyl. Clin. Allergy 15: 234-240).
Recently, compounds such as benzyl benzoate, paragerm and the like have been used as acaricides (Penaud, A., J. Nourrit, P. Timon-David and J. Charpid. 1977. Results of a controlled trial of the acaricide paragerm on Dermatophagoides spp. In dwelling houses. Clin. Allergy 7: 49-53; Schober, G., G. Wetter, E. Bischoff, J. E. M. H. van Bronswijk and F. M. Kniest. 1987. Control of house dust mites(Pyroglyphidae) with home disinfectants. Exp. Appl. Acarol. 3: 179-189).
It has been reported that many plant extracts and oils have characteristics of repellence of egg and insecticidal activity for various stored products. It has been reported that oils derived from Acorus calamus have insecticidal activity against Callosobruchus chinensis, Sitophilus oryzae, Sitophilus granaries, Tribolium confusum, and Rhizopertha dominica F (El-Nalhal, A. K. M., Schmidt, G. H., Risha, E. M. 1989. Vapours of Acorus calamus oil-a space treatment for stored-product insects. J. Stored Prod. Res., 25:211-216). And also, compounds derived from plants have characteristics of potent insecticidal activity for insecticide-resistant pests (Arnason, J. T., Philogene, B. J. R., Morand, P., Lmrie, K., Lyengar, S., Duval, F., Soucy-Breau, C., Scaiano, J. C., Werstiuk, M. H., Hasspieler, B., downe, A. E. R. 1989. Naturally occurring and synthetic thiophenes as photoactivated insecticides. In Insecticides of Plant Origin, eds. by Arnason, J. T., Philogene, B. J. R., Morand, P. ACS symposium Series 387:164-172). And, Ginkgo biloba leaf extracts have characteristics of potent insecticidal activity against carbofuran, fenobucarb and diazinon-resistant Nilaparvata lugens (Ahn, Y. J., Kwon, M., Park, H. M., Han, C. G. 1997. Potent insecticidal activity of Ginkgo biloba-derived trilactone terpenes against Nilaparvata lugens. In Phytochemical Pest Control Agents, eds. by Hedin, P., Hollingworth, R., Miyamoto, J., Masler, E., Thompson, D., ACS Symposium series 658:90-105).
Most plant extracts and oils having these activities belong mainly to monoterpenes or phenylpropanoids (Coats J, R., karr, L. L., Drewes, C. K. 1991. Toxicity and neurotoxic effects of monoterpenoids in insects and earthworms. In Naturally Occurring Pest Bioregulators, eds. by P. A. Hedin. ACS Symp. Ser. 449:305-16; Konstantopoulou, L., Vassilopoulou, L., Mauragani-Tsipidov, P., Scouras Z. G. 1992. Insecticidal effects of essential oils. A study of the effects of essential oils extracted from eleven Greek aromatic plants on D. auraria. Experientia. 48:616-9; Regnault-Roger, C., Hamraoui, A., 1995. Fumigant toxic ativity and reproductive inhibituin induced by monoterpenes on Acanthosceides obtectus(Say) (Coleoptera: Bruchidae) a pest of kidney bean(Phaseolus vulgaris L.). J. Stored Prod. Res. 31:291-299).These chemical compounds show insecticidal activities against insect species through high volatility. Carvacrol, monoterpenoid isolated from saw dust of Thujopsis dolabrata, showed volatile action against agricultural pests and hygienic pests as well as stored-product insects (Ahn, Y. J., Lee, S. b., Lee, H. S., Kim, G. H. 1998. Insecticidal and acaricidal activity of carvacrol and β-thujaplicine derived from Thujopsis dolabrata var. hondai sawdust. J. Chem. Ecol. 24:81-90).
Control against stored-product insects is mainly dependent on the continuous treatment of liquid agents or fumigants and control of mites has been primarily dependent on chemical acaricides.
Repetitive treatments of these chemical agents have been used for several decades, resulting in generation of resistant species against various types of pesticides and causing adverse effects to environments and humans. Some stored-product insects have developed the resistance for fumigants such as methyl bromide and phosphine, and especially mites of Pyroglyphidae species having resistance to both DDT and lindane have been found. So, research has been carried out to find alternatives for these agents. In order to develop natural acaricides much effort has been focused on plant materials used for folk remedies as well as aromatic compounds having pleasant perfume. (Miyazaki, Y., M. Yatagai, and M. Takaoka. 1989. Jpn. J. Biometeor. 26: 105-108; Watanabe, F., S. Tadaki, M. Takaoka, S. Ishino and I. Morimoto. 1989. Killing Activities of the volatiles emitted from essential oils for Dermatophagoides pteronyssinus, Dermatophagoides farinae and Tyrophagus putrescentiae. Syoyakugaku Zasshi 43: 163-168; Yatagai, M. and S. Morita. 1991. Extractives from Yakusugi bogwood and their termicidal activity and growth regulation effects on plant seeds. Mokuzai Gakkishi J. Japan Wood Res. Soc. 37: 345-351; Morita, S., M. Yatagai and T. Ohira. 1991. Antimite and antifungal activities of the hexane extractives from yakusugi bogwood. Journal of the Japan Wood Research Soc. 37(4): 352-357).